Welding & Fabrication worked example

Sheet Metal Bend Allowance with bend angle in radians of 0.79 rad: a worked example

This worked example runs the sheet metal bend allowance numbers for a tougher week than the baseline: bend angle in radians of 0.79 rad instead of the typical 1.57 rad. Estimate sheet metal bend allowance from bend angle (radians), inside bend radius, material thickness, and K-factor.

The inputs for this scenario

  • Bend angle in radians: 0.79 rad (the input this scenario stresses; the baseline uses 1.57)
  • Inside bend radius: 0.13 in (held at the documented default)
  • Material thickness: 0.07 in (held at the documented default)
  • K-factor: 0.42 x (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Combined bend zone term = inside bend radius × material thickness × K-factor.
  • Sheet metal bend allowance estimate works out to 0 in at these inputs, and this is the headline figure for the scenario.
  • Base product works out to 0.01 value at these inputs.
  • Multiplier works out to 0.42 x at these inputs.
  • Factor A x B works out to 0.1 value at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where bend angle in radians sits at 1.57 rad and the headline result is 0.01 in, this scenario comes in 49.71% below the baseline at 0 in.
  • Use it when developing a flat pattern for a press-brake part, so the blank length accounts for material consumed in each bend. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • Sheet metal bend allowance estimate: 0 in (headline result)
  • Base product: 0.01 value
  • Multiplier: 0.42 x
  • Factor A x B: 0.1 value

Run it with your numbers

  • To rerun this with your own numbers, open the live Sheet Metal Bend Allowance calculator, set bend angle in radians to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.